81533027212 has 144 divisors (see below), whose sum is σ = 185727209472. Its totient is φ = 30622475520.

The previous prime is 81533027167. The next prime is 81533027231. The reversal of 81533027212 is 21272033518.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7769433 + ... + 7779919.

It is an arithmetic number, because the mean of its divisors is an integer number (1289772288).

Almost surely, 2^81533027212 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 81533027212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (92863604736).

81533027212 is an abundant number, since it is smaller than the sum of its proper divisors (104194182260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

81533027212 is a wasteful number, since it uses less digits than its factorization.

81533027212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10608 (or 10593 counting only the distinct ones).

The product of its (nonzero) digits is 20160, while the sum is 34.

The spelling of 81533027212 in words is "eighty-one billion, five hundred thirty-three million, twenty-seven thousand, two hundred twelve".